Laparoscopic, thoracoscopic and other endoscopic procedures are well-known, widely utilized surgical techniques that advantageously reduce patient recovery time due to minimal tissue damage. Generally, these surgical techniques rely upon the formation of one or more puncture wounds through which a body cavity, such as the peritoneal or the thoracic cavity, can be accessed. In laparoscopic surgery, once the peritoneal cavity has been entered, the same is insufflated with carbon dioxide gas, typically to a pressure of approximately 15 mm Hg, followed by the introduction of an endoscopic port with inserted trocar, which may either be bladed or blunt. In thoracoscopic surgery, once the thoracic cavity has been entered, procedures can be performed either by the selective deflation of the lung on the side of the operation with subsequent placement of an endoscopic port, or by the creation of a controlled pneumothorax by insufflation of a limited amount of carbon dioxide gas through a port that is placed into the thoracic cavity which has an airtight seal.
In these procedures the port and cannula are essentially the same and function to accept by insertion a trocar for tissue penetration or an endoscope for viewing. Generally the terms laparoscope, thoracoscope, mediastinascope, arthoscope and other such viewing device will be referred to herein using the generic term ‘endoscope’.
The endoscopic port with inserted trocar is placed into the peritoneal, thoracic or other body cavity, followed by the placement of a viewing device therethrough to thus provide visualization of the body cavity thus enabling the surgeon to view the surrounding organs and conduct the surgical procedure. Advantageously, the use of such ports placed through small diameter openings enables the patient to readily heal following surgery, and requires much less recuperation time for the patient as compared to open surgical procedures, which typically deploy long incisions which can and frequently are deemed traumatic to the patient and involve substantially longer recuperative periods. Despite its advantages, endoscopic surgery as currently performed can pose substantial risks to the patient. In this respect, it is widely recognized that entry into the body cavity during such surgery, due to the procedure by which the body cavity is accessed, can cause serious injury, for example, to the abdominal organs, such as the spleen, liver and intestine as well as blood vessels, or to the thoracic organs, such as the lung, heart, or blood vessels. In the abdomen, this risk is due in large part to the fact that in the unoperated abdomen, most surgeons enter the peritoneal cavity using a Veress needle which is pushed blindly through the patient's fascia and peritoneum. The peritoneal cavity is then insufflated followed by the introduction of the laparoscopic port with inserted blunt or bladed trocar, which also is pushed blindly into the peritoneal cavity. Once positioned therein, the trocar is removed and a laparoscope is introduced through the port to thus provide visualization within the cavity.
Problematic with such procedure, however, is the fact that the body cavity is entered blindly on two separate occasions: first, through the introduction of the Veress needle; and second, through the introduction of the laparoscopic port with inserted trocar, which can and on occasion does injure abdominal organs and blood vessels.
To the extent laparoscopic surgery is performed upon a patient that has previously undergone an abdominal operation, the preferred surgical practice is to enter the peritoneal cavity under direct vision. In this regard, it is known that when a patient has undergone previous abdominal surgery, the abdominal contents can become adherent to the abdominal wall, making blind placement of a Veress needle and then blind placement of the port with inserted trocar a much more risky technique.
Using a direct vision technique, the skin is incised and the subcutaneous tissue dissected until the fascia is encountered. The fascia is then dissected, typically by grasping the fascia with two surgical clamps and incising the fascia sharply followed by successively grasping the subfascial tissue until the peritoneum is encountered at which point the peritoneum is opened and the peritoneal cavity is entered under direct visualization. Once entered, the laparoscopic port is then placed in the peritoneal cavity under direct vision and the abdomen insufflated with carbon dioxide gas. This procedure, however, typically requires a larger skin incision than is typically produced via the use of the Veress needle technique, particularly with respect to obese patients, and is further more prone to gas leakage during surgery, thus requiring constant monitoring and maintenance of adequate insufflation.
In light of such potential complications that can arise via entry into the peritoneal cavity during laparoscopic surgery, attempts have been made to provide means for safely entering into a body cavity utilizing direct visualization. Exemplary of such devices are those disclosed in U.S. Pat. No. 5,441,041, issued to Sauer, et al., entitled Optical Trocar, issued Aug. 15, 1995, which utilizes a blade moveable between a non-deployed position and a deployed position to thus allow dissection under visualization of an endoscope. Such device, however, does not allow for any type of spreading of the cut tissue to enable the surgeon to see the next layer of tissue to be entered. As such, dissection is performed without prior visualization thereof.
A similar device attempting to provide direct visualization during entry into a body cavity is shown in U.S. Pat. No. 5,569,291, issued to Privitera, et al., entitled Surgical Penetration and Dissection Instrument, issued on Oct. 29, 1996. Such reference discloses a device for forming an entry into a body cavity performed under direct visualization of an endoscope. The dissecting portion of the device consists of a clear plastic conical tip with elevated dissecting blades that is advanced into the tissue via a twisting motion. The conical tip, however, is advanced bluntly into the tissue before the same can be identified and, as a consequence, incision of the tissue is performed without prior visualization. In fact, inadvertent entry into an organ cannot be avoided via use of such device, and it is only after the organ is entered, and hence damaged, that such matter can be appraised. Moreover, the use of clear plastic has substandard optical visualization due to optical properties inherent in such material, coupled with the conical shape, such that advancement of the tip fails to provide a clear visualization as the same is advanced through tissue.
Other devices that are similar in nature include U.S. Pat. No. 5,720,761, issued to Kalli on Feb. 24, 1998 entitled Visually Directed Trocar and Method; U.S. Pat. No. 5,551,947, issued to Kalli on Sep. 3, 1996, entitled Visually Directed Trocar for Laparoscopic Surgical Procedures and Methods of Using the Same; U.S. Pat. No. 5,609,562, issued to Kalli on Mar. 11, 1997 entitled Visually Directed Trocar and Method; and U.S. Pat. No. 5,385,572, issued to Nobles, et al. on Jan. 31, 1995 entitled Trocar for Endoscopic Surgery, the teachings of all of which are expressly incorporated herein by reference.
A further related surgical instrument is disclosed in U.S. Pat. No. 5,354,302, issued to Ko entitled Medical Device and Method for Facilitating Intra-Tissue Visual Observation and Manipulation of Distensible Tissues. Essentially, such device comprises an elongated sheath having a cone-shaped distal end and inner sheath member disposed therein within operative to cause the distal end to move tissue away to thus enable tissue to be manipulated and visualized by the inner sheath member. While the cone-shaped distal end is operative to move tissue away such that visualization of tissues and the like can be enhanced, such cone-shaped distal end does not provide any dissection function. Indeed, the flaps of the distal end of the cone member are flimsy in nature and non-reinforced. As such, the same are ill suited for enhancing direct visualization, much less providing any type of dissecting function. Such device is further not designed for use in laparoscopic applications, and in particular a laparoscopic port through which other instruments can be positioned and deployed.
There is thus a substantial need in the art for a system and method that can enable a surgeon to selectively enter a body cavity, vessel, or organ, for purposes of performing endoscopic procedures whereby the surgeon is provided with direct visualization during entry such that tissue separation can be visualized and organ and tissue damage can be avoided (i.e., the surgeon can see the tissue prior to dissecting the same). There is additionally a need for such a device and system that is capable of forming an entry into a body cavity via a skin incision no greater than that required to admit the introduction of an endoscopic port and that also preferably forms a tight seal around the port following its introduction such that gas leakage during the surgical procedure is minimized. Still further, there is need for such a system and method which provide for cavity entry without prior insufflation of gas into the cavity but can preferably have a means to insufflate the body cavity following entry, if desired.